This proposal requests funds to replace a standard confocal microscope that supports the research of investigators affiliated with two multi-disciplinary research centers at the University of Washington. The Center for Human Development and Disabilities and the Virginia Merrill Bloedel Hearing Research Center have jointly managed a microscopic imaging core facility since 1995. This facility has been well supported since its inception by NIH P30 grants, individual investigator grants, and institutional funds. The Bio-Rad MRC-1024UV confocal microscope, purchased in 1994, has been a workhorse for this large group of productive investigators. Despite its having out- of-date technology, this instrument has supported more than 25 research publications in the past 5 years. Unfortunately, this group of investigators can no longer depend on this early generation confocal system to reliably facilitate completion of funded research aims. Service and software upgrades are no longer possible, and down-time has led to a significant usage backlog and subsequent overuse of alternative equipment available to some investigators. The major and minor users on this application represent 13 departments in both clinical and basic sciences. The scientific questions they pursue range from identifying molecular determinants of early embryonic development to characterizing disease-modifying genes involved in infection, hearing loss, and neurological disorders. Several investigators in this group are conducting translational research projects in brain tumors, central nervous system injury, and neurodegeneration. The major scientific impetus behind this application is the need for reliable access to increased confocal microscopy time. However, research performed by this group will also be greatly enhanced by access to modern confocal technologies, including but not limited to, spectral unmixing, user- defined region of interest scanning, 360-degree scanning rotation, improved resolution in both time and space, and dramatic improvements in the efficiency of image acquisition. [unreadable] [unreadable] [unreadable]